This exercise crosses all 4 strings, outlining first a dominant 7 sus 4 chord (starting on B7sus4), then resolving the sus 4 to the 3rd (actually an 11th to a major 10th). Note that your thumb will act as a pivot to do this arpeggio, and that your elbow should be away from your body so that you can sweep it slowly back and forth. This allows your wrist to move back and forth with minimum wasted motion, almost as if you were rocking a baby one-handed.
The key is to keep your wrist and shoulders relaxed, and let your fingers reach out across the neck for the lower notes, gently curved, and then remain curved as you pivot for the higher notes, so that the fingers are parallel with the neck.
Continue the exercise all the way down the neck. Once you have this mastered, start further up the neck.
